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Date:   Fri, 13 May 2022 16:32:12 +0800
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Subject: [PATCH v3 2/3] kunit: Taint the kernel when KUnit tests are run
From:   David Gow <davidgow@google.com>
To:     Brendan Higgins <brendanhiggins@google.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kees Cook <keescook@chromium.org>,
        Shuah Khan <skhan@linuxfoundation.org>,
        Greg KH <gregkh@linuxfoundation.org>,
        Luis Chamberlain <mcgrof@kernel.org>
Cc:     David Gow <davidgow@google.com>,
        "Guilherme G . Piccoli" <gpiccoli@igalia.com>,
        Sebastian Reichel <sre@kernel.org>,
        John Ogness <john.ogness@linutronix.de>,
        Joe Fradley <joefradley@google.com>,
        Daniel Latypov <dlatypov@google.com>,
        kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Lucas De Marchi <lucas.demarchi@intel.com>,
        Aaron Tomlin <atomlin@redhat.com>,
        linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org
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Precedence: bulk

Make KUnit trigger the new TAINT_TEST taint when any KUnit test is run.
Due to KUnit tests not being intended to run on production systems, and
potentially causing problems (or security issues like leaking kernel
addresses), the kernel's state should not be considered safe for
production use after KUnit tests are run.

Signed-off-by: David Gow <davidgow@google.com>
---
 lib/kunit/test.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index 0f66c13d126e..2b808117bd4a 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -11,6 +11,7 @@
 #include <kunit/test-bug.h>
 #include <linux/kernel.h>
 #include <linux/moduleparam.h>
+#include <linux/panic.h>
 #include <linux/sched/debug.h>
 #include <linux/sched.h>
 
@@ -498,6 +499,9 @@ int kunit_run_tests(struct kunit_suite *suite)
 	struct kunit_result_stats suite_stats = { 0 };
 	struct kunit_result_stats total_stats = { 0 };
 
+	/* Taint the kernel so we know we've run tests. */
+	add_taint(TAINT_TEST, LOCKDEP_STILL_OK);
+
 	kunit_print_subtest_start(suite);
 
 	kunit_suite_for_each_test_case(suite, test_case) {
-- 
2.36.0.550.gb090851708-goog